package com.heima.admin.gateway.filter;

import com.heima.admin.gateway.utils.AppJwtUtil;
import io.jsonwebtoken.Claims;
import org.apache.commons.lang.StringUtils;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.http.HttpStatus;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.stereotype.Component;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;

@Component
public class AuthorizeFilter implements GlobalFilter {
    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        //1.拿到请求和响应对象
        ServerHttpRequest request = exchange.getRequest();
        ServerHttpResponse response = exchange.getResponse();
        //2.判断本次请求是否是登录相关资源:是,则执行放行
        if (request.getURI().getPath().contains("/login")){
            return chain.filter(exchange);
        }

        try {
            //3.不是登录,需要进行token验证
            //4.先获取到token
            String token = request.getHeaders().getFirst("token");

            //5.验证token是否有效:a.不能为空;b.不能过期;c.解析不能出错;不通过统一返回:401
            if (StringUtils.isEmpty(token)) {
                response.setStatusCode(HttpStatus.UNAUTHORIZED);
                return response.setComplete();
            }
            Claims claimsBody = AppJwtUtil.getClaimsBody(token);
            //Object appUserId = claimsBody.get("id");
            int res = AppJwtUtil.verifyToken(claimsBody);
            if (res == 1 || res == 2) {
                //b.不能过期
                response.setStatusCode(HttpStatus.UNAUTHORIZED);
                return response.setComplete();
            }

            //没过期：将token解析得到用户id，并且存入request的header头，转发给下游微服务
            Object userId = claimsBody.get("id");
            //在header中添加新的信息
            ServerHttpRequest serverHttpRequest = request.mutate().headers(httpHeaders -> {
                httpHeaders.add("userId", userId + "");
            }).build();
            //重置header
            exchange.mutate().request(serverHttpRequest).build();

        }catch (Exception e){
            e.printStackTrace();
        }
            //6.验证都通过了就放行

        return chain.filter(exchange);
    }
}
